Everything on the Internet said to keep them separated, switching rooms regularly so they can still smell each other, and then slowly reintroduce them, a process which can take days. But I'm going out of town on Thursday; we don't have days. Any advice is welcome. :\
Update: On advice from my friend A, I let Lexi out while watching both kitties like a hawk, and after some hissing and posturing, everyone settled down and we seem to have relative peace. I'm still wary, but the situation is stable anyway. Let's hope they work this out on their own now, another night like last one is not really on my wishlist.
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